Christopher Schultz wrote:
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
Chuck,
On 3/23/15 10:33 AM, Caldarale, Charles R wrote:
From: Christopher Schultz [mailto:ch...@christopherschultz.net]
Subject: Re: Tomcat 7 (7.0.54) memory consuption is very high(3
times) than Tomcat 6 (6.0.28)
Really? The Tomcat ROOT web application is taking up 3 times as
much heap space in Tomcat 6 as Tomcat 7?
Just remember that the numbers out of top are at best
approximations, and, as Rainer pointed out, not taking measurements
immediately after a GC is a guarantee of an apples versus oranges
comparison.
The appropriate tools (e.g., VisualVM) must be used for any
rational analysis.
+1
The output of "top" and "ps" are completely irrelevant. The very
minimum would be the output of "jmap -heap", and only after a full GC
were to have been run.
The appropriate java-specific tools must certainly be used to find out /what/ is using
this memory inside the JVM.
But qualifying the output of "top" or "ps" as "irrelevant" is probably a bit
over the top.
After all, they do indicate how much the JVM is (approximately) using from an OS
perspective, and that is probably not totally irrelevant here.
I wanted to see the respective startup commands to check if there wasn't some change in
the default startup script switches (like -Xms/-Xmx) which would explain the difference.
But apparently not.
Even if a GC would make the two look less different, the question would remain as to why
one Tomcat would need a GC for that, and the other not.
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org
